The present invention relates to a method of controlling the temperature of molten steel and the carbon content in an oxygen converter.
As is known, in the blowing operation in the oxygen converter, it is customary to stop the blowing process whenever the molten steel has attained the desired temperature and carbon content. Actually, however, it is difficult to accurately attain the desired temperature and carbon content. For this reason, feeding of oxygen is stopped immediately before the predicted blow-stopping time when the desired levels are attained, and the converter may be tilted to measure the temperature and to take a sample analysis. This method, however, is inefficient and therefore impractical. Comparatively lately, there is proposed a method in which using a sub-lance, a detection probe is immersed into the molten steel immediately before the predicted blow-stopping time to simultaneously measure the temperature of the molten steel and the carbon content, and from the measured values thereof the variation in temperature and the variation in carbon content may be predicted using a static model and to thereby control the feeding of oxygen and to throw or charge the auxiliary raw material or flux in order to attain the desired values. In the static model as noted above, however, the decarburization rate and variation in temperature rise of the molten steel are all analyzed primarily in connection with the amount of blowing oxygen, and consequently, in the actual blowing operation, the rate to hit the desired values is excessively low and in addition, irregularities often occur.